1. Field of the Invention
The present invention concerns an image processing device for an expanded representation of a three-dimensional image data set, in particular of a three-dimensional image data set from medical imaging, with an image presentation module that is fashioned for 3D representation of a 3D subject on an image display device and an interaction module via which an operator can interactively displace, rotate or zoom the 3D subject in the 3D representation.
2. Description of the Prior Art
Computer graphic systems are known with which (3D) objects and scenes can be shown on a presentation module. The representation of the objects can be manipulated in versatile manners, for example by rotation, translation or zooming. To improve the realistic impression of an object or of a scene, various exposure situations as well as reflections of the object on the surface of other objects are shown. Algorithms known as ray tracing algorithms (ray tracing) and radiosity methods based thereon are used (see “Graphics: Reflection Model, Graphics Lab, Korea Univ., 2004, 41 sheets+bibliography (http://kucg.korea.ac.kr/˜sjkim/teach/2004/COMP365/lecture/07reflection.ppt)” or A. Iwansky et al., “Lexikon der Computergraphik und Bildverarbeitung”, Vieweg 1994, p. 18, 56-58, 231-234, 237, 249-250, 274, 306). A computer program suitable for realistic representation of 3D objects is Persistence of Vision™ Ray Tracer, POV-Ray™ version 3.1g, “User's Documentation”, POV-Team, 1999, p. 1-17, 23-29, 54-69, 82, 97-101, 136-138, 177-182, 250-256, 294-300, 317-320.
The 3D representation of 3D objects represents an important tool in many technical fields, for example in the field of medical imaging and in the design of technical apparatuses. For example, radiologists and surgeons use 3D visualization devices for assessment and planning of operations, the 3D visualization devices showing anatomical regions of interest of a patient three-dimensionally in perspective representation on a monitor using volume rendering techniques (VRT) on the basis of a medical 3D image data set obtained from the patient. By suitable tissue specifications it is thereby possible to display to the physician only the structures of interest (for example only the vessels) of the examined region or of the region encompassed by the 3D image data set. With the available means the physician must then determine from this 3D representation the information that is relevant to him or her. For example, this may be vessel stenoses, and their position and orientation relative to other vessels etc.
For this purpose the visualization device normally has an interaction module with which the operator can rotate, displace or zoom the shown volume interactively in all spatial directions. During the assessment and planning these steps are often repeated multiple times, since it is very often necessary to consider the subject of interest from all sides. These repeated interactions can be very time-consuming depending on the problem.